Snatch block



June 1942.

c. K. STILLWAGQN SNATCH'BLOCK Filed Nov.

Patented June 30, 1942 stares This invention relates to a snatch block.

The invention herein described includes certain improvements over thattype of snatch block described in Patent No. 2,235,302 issued by theUnited States Patent Office tothe applicant herein on March 18, 1941.

An object of the invention is to provide equipment of the characterdescribed embodying a frame and a sheave adapted to receive a cable androtatably mounted on the frame, said frame having one of its side plateshinged and releasably connected with the corresponding end of the sheavespindle, by novel connecting means, and whereby upon release of saidconnecting means the hinged side plate may be swung to 5 open positionto facilitate the mounting of the cable on, or its removal from, thesheave.

Another object of the invention is to provide in a snatch block a noveltype of sheaving spine dle anchored to the unitary side plate, in anovel manner, so as to hold the spindle against turning.

It is another object of the invention to provide a swiveling nut looselyanchored to the hinged side plate and which may be readily connected toor disconnected from the corresponding end of the sheave spindle withco-acting means carried by the nut and spindle for centering the nutrelative to the spindle to facilitate the connect ing of the hinged sideplate to the spindle.

Provision is also made for lubricating the Figure 2 shows an edge viewpartly in longi- 1 tudinal section showing the hinged side plate securedin closed position.

Figure 3 shows an enlarged longitudinal sectional view, and

Figure 4 shows an enlarged fragmentary side 1 elevation.

Referring now more particularly to the drawing wherein like numerals ofreference designate the same parts in each of the figures, the nu merall designates one of the side plates of the frame. This side plate isapproximately elliptical in form and is of unitary structure. The

other side plate is of approximately the same contour as that of theplate I but is formed of two sections, 2 and 3, which are hingedtogether on the transverse pin 4. Between the stationary section 2 andthe plate I there is a swivel block 5 having the end spindles as 6, 6which extend through aligned bearings of the respective plates and whoseouter ends are threaded to receive the nuts I, l. The block 5accordingly may swivel with respect to the frame. The block 5 has abearing 8 therethrough to receive the shank 9 of the hook H3. The innerend of the hook is threaded to receive a retaining nut ll thereonwhereby the hook It may also swivel relative to the block 5.

There is a sheave spindle [2 one end of which is reduced and fittedthrough a hole [3 in the plate I. The reduction of said end forms ashoulder which seats against the inside of the plate I as shown inFigured Said reduced end is externally threaded to receive the retainingnut I4 and fitted around said reduced end and clamped between the nut Itand the adjacent side of the plate l there is a soft metal washer l5which is slightly compressed when the nut i4 is screwed home and whichserves as a lock to prevent the nut I4 from readily unscrewing.

At one side the reduced end of the spindle i2 is formed with atransverse keyway l6 presenting a flat face IT and opposite this keywaythe plate I has an external arcuate countersunk portion 18 into which acorrespondingly shaped key It is fitted, said key having a flat facewhich fits against the face ll. The washer l5 overlaps the key l9 andholds it firmly in place and the key securely holds the spindle 12against rotation.

Driven onto the spindle I2 and located between the side plates of theframe there is a bearing sleeve 2!] formed of bronze or other similarmaterial on which the sheave 2! is mounted to rotate.

The other end of the spindle i2 is reduced and adapted to be fittedthrough a hole 22 in the section 3 of the hinged side plate, saidreduced end extending beyond said section and being externally threadedand also being provided with an axial socket 23 whose outer end isoutwardly flared.

Rotatably mounted on the outer ,side of the section 3 there is a nut 24.This nut has an internally threaded inside socket to receive thecorresponding externally threaded end of the spindle l2. The nut 24 isconnected to the hinged section 3 of the side plate so as not to becomedetached therefrom in order that the nut will not become lost inhandling the snatch block about the derrick or other place of use. Asone means for attaching the nut to the side plate the inner end of thenut may be provided with an external annular rib 25 and welded, orotherwise fastened to the side plate there is an annular flange 26 whoseouter margin is overturned forming a rim 2! which extends over the rib25 whereby the nut 24 is connected to the side plate to swivel and isheld against detachment therefrom.

The nut 24 has an inwardly extended stud 28 forming a guide which fitsinto the socket 23 and serves to guide the nut 24 into proper alignmentwith the externally threaded end of the spindle l2 so that the nut 24may be screwed onto said threaded end without the threads becomingcrossed. If it be desired to remove a cable from, or place a cablearound, the sheave 2|, the nut 24 may be unscrewed. As the hingedsection 3 moves outwardly it will move in an are about the pin 4, butthe nut 24 being loosely mounted on the section 3 may move in a trueaxial direction relative to the spindle l2 until its threads have becomedisengaged from the spindle threads. When said threads are completelydisengaged, the section 3 may be swung outwardly so that the cable maybe easily removed from, or a cable may be placed around, the sheave 2|.

When the cable has been mounted on the sheave the hinged section 3 maythen be swung into closed position and the guide 28 will guide the nut24 into exact axial relationship with said spindle and said nut 24 maythen be screwed onto the threads of the spindle so as to secure theplate section 3 on the spindle end to retain the cable in place.

The drawing and description are illustrative merely while the broadprinciple of the-invention will be defined by the appended claims.

What I claim is:

1. A snatch block comprising a frame composed of approximately parallelside plates one of which is formed of a fixed section and a hingedsection and the other of which is unitary, a swiveling block locatedbetween and connected to said unitary plate and the fixed section of theother plate, attaching means on the block, a sheave spindle havingextended ends, one of said ends extending through the unitary plate, anut threaded onto said extended end and securing the spindle to theunitary plate, a key between the spindle and unitary plate efiective tohold the spindle against turning, the other end of the spindle extendingthrough said hinged section and being externally threaded, a nut, meanson said hinged section for loosely mounting said nut to swivel, said nuthaving internal threads adapted to mesh with the external threads of thespindle for holding the hinged section in supporting relation with thecorresponding end of the spindle and a sheave rotatably mounted on thespindle between said plates.

2. A snatch block comprising a frame composed of approximately parallelside plates one of which is formed of a fixed section and a hingedsection and the other being unitary, means for maintaining the unitaryplate and the fixed section together and in spaced relation, a sheavespindle one end of which is secured to the unitary plate and the otherend of which is extended through the hinged section and is provided withan internal socket and external threads, a nut, means on the hingedsection for loosely mounting said nut to swivel, said nut havinginternal threads adapted to mesh with I CRAWFORD K. STILLWAGON.

